For the lamination of a decorative metal film, the resin base materials used in applications such as in electronic devices, home appliances, and exteriors and interiors of automobiles are subjected to a surface treatment whereby a thin film of about 10 μm thick is laminated using methods such as a coating method, and a decorative metal film is laminated thereon to provide the feel and appearance of a metal, using a wet plating method, a sputtering method, or a vacuum deposition method.
One of the problems of the coating method, however, is that it uses organic solvents and is therefore harmful to the environment. Another problem is the cost and the poor yield. Further, the coating method presents difficulties in continuously performing processes such as sputtering after the surface treatment, preventing the reduction of the installation area of the deposition apparatus.